Four-year-olds use eye-gaze cues to detect deception

December 2004, Vol 35, No. 11

Print version: page 12

The eyes may be windows to a deceiver's soul, but children don't begin to realize that until they are about 4 years old, according to a study in the November issue of APA's Developmental Psychology (Vol. 40, No. 6).

Kang Lee, PhD, a psychology professor at the University of California, San Diego, sought to determine whether young children could follow a person's eye gaze to pinpoint the location of a hidden toy--particularly if the children knew that the person was trying to trick them.

To find out, Lee and his colleagues tested 97 children who were 3 to 5 years old. The researchers told the children that they were going to play a hide-and-guess game with a videotaped, "tricky" person named Julie. On the video, Julie explained that she was going to hide a squeaky toy in one of three cups. After a brief blank screen, Julie and the three cups reappeared. Julie said that she did not know which cup held the toy, but she looked at the correct cup.

The 4- and 5-year-olds then correctly identified the location of the toy at rates much better than chance, but 3-year-olds did not. The researchers repeated the task three times with each child. Among 4- and 5-year-olds, 34 of 65 children found the toy during all three trials, while only three of 32 3-year-olds did the same.

When the researchers repeated the experiment with a different clue--Julie put her hand over the correct cup--the 3-year-olds' performance improved. This time, 22 of the 32 3-year-olds found the toy every time (as did 61 of the 65 older children).

These findings add to the larger picture of how and when children begin to use eye-gaze cues, says Lee. Infants are sensitive to eye gaze from birth, he says--they know when someone is looking directly at them. By their 12th month, toddlers begin to follow an adult's gaze, and they use that skill to learn language--for example, learning the word "apple" by hearing the word as they watch an adult look at an apple.

At 18 to 24 months, children begin to use eye-gaze cues to infer another person's mental state--for example, to figure out which one object among many another person is interested in.

But Lee's study illustrates that toddlers still don't fully understand the extent of what eye gaze can reveal. "Three-year-olds don't yet pay attention to some of the eye-gaze cues that older children and adults use to uncover deception," he says.